Improvement in grate-bars for furnaces



E. MALLON.

Grate-Bars for urnaces.

Patented Feb. i7, i874.

I ivriED STATES PATENT OFFICE.

RDwARD MALLoN, or NRW roRK, N. Y.

lMPROVEVIENT IN GRAT-BARS FOR FURNACES.

Specication forming part of Letters Patent No. llio, dated February 17,1874; application filed J annary` 26, 1874.

To all whom it may concern:

Be it known that I, EDWARD MALLON, of the city and county of New York,in the State of N ew York, have invented certain new and usefulImprovements in Grate-Bars for Furnaces, of which the following is aspecification: e

My invention relates to grate-bars in which each bar is supported uponthe other without intermediate bearers; and the invention which is thesubject of this patent consists ot' dovetail openings, formed throughthe grate-bars,

for the twofold purpose of receiving dovetail projections from theadjacent bars and forming air-openings for the grate 5 also, ofthereceiving doveta-il openings having enlarged entering portions for theheads ofthe dovetail projections, and lower socket-seats for the shanksthereof, whereby, in placing the bars side by side, their enlarged headsare inserted through the openings and their shanks drop down into narrowsocket-seats to support the bars, and hold them in place and preventthem from warping or twisting; and of the spacing-lugs, combined with,and forming backs to, the reeeiving dovetail openings of the bars togive strength to the bars at these openings, thereby utilizing theordinary lugs, which form the spaces between the bars for the two.additional purposes and advantages stated.

In the accompanying drawings, Figure l represents a view, inperspective, of several of the grate-bars locked together by dovetailingdevices; Fig. 2, a similar view of the opposite side of one of the bars;Fig. 3, a crosssection of several of the bars taken through `.the lugsand dovetailing locking devices; and Fig. 4, a horizontal section of thesame.

rlhe bars are cast in the usual manner, with vertical lugs a on oneside, running from the top to the bottom, for giving the required airand raking spaces to the grate. These lugs, in addition to thisfunction, serve as the bases upon which to cast dovetail projections b,standing out from the face of each lug a, and with their shoulders ceither beveled or parallel to the side of the bar. In the dn wings Ihave shown these dovetails b as having a projection equal to thethickness of the bars, (but they may be less, if desired,) and they aresufficiently strong to support the bar.

In each bar, directly opposite the lugs, dovetail open-` ings d areformed to receive the dovetail projections b, and to lock them therein.For this purpose the upper portion e ot' the openings d are enlarged7 soas to form an outline' like the letter T, in which the lower portion fis to receive and hold the shank g of the lug dovetail. while theenlargement is to admit of the entrance of the dovetail-head h, to allowthe shank g to be passed into and seated upon the socketseat t' of theopen dovetail, in which positions the neck j' of the socket-seatsdovetail with the shoulders c of the lug projections, and this matching,while supporting one bar upon the other, locks them all laterally, sothat they cannot spread by warping or twisting, and also prevents theirmoving endwise out of place. There is sufficient play, however, betweenthe dovetail shanks g and the dovetail necks j" to allow each bar tohave an endwise movement to compensate for the expansion of the bars,and to admit of their easy connection in laying the grate. The receivingdovetails d although made in the body of the bars are prevented fromweakening them by the lugs a., which, crossing these openings dvertically, form backs 7c thereto, and strengthen the bars at thesepoints, and render the openings d ot' advantage as ventilators to thegrate. By this invention it is only required to have lugs on one side ofthe grate-bar, and these lugs are integral with the supportingdovetails. Short lugs Z are also cast upon the same side near the endsof the bars. The supporting dovetailing devices are, of course, arrangedat such distances apart according to the length of the grate-bars. Thenthe bars are laid together they cannot be separated, except by liftingeach bar separately to disen gage the dovetail from its receivingsocket-seat and then drawin git away sidewise; and, in'setting them, theprojecting dovetails are inserted in place on the plain side of eachbar, so that the head ot' each dovetail will join the back of each lugas each bar is putin place. The finishing end bar has lugs on both sidesand no dovetails, so that it can be readily inserted in place betweenthe bars and the furnace-wall, as shown in Fig. 3.

Then the grate is laid no single bar but the last one can be removed;and all the bars are supported so that neither can fall out or be pulledapart. They can only be separated by raising eaeh Separate grate-bar tobring the head of the dovetail b opposite the enlarged part Ot' thereceiving. dovetail. The grate is set and supported at its end upon thewall in the usual manner.

In settin g the bars,the dovetails are entered laterally, and JtheirShanks dropped into the dovetails or socket-seats, and each bar ear-riesits entering and receiving dovetail devices7 und in these respects iscomplete in itself.

I claiml. rlhe dOvet-ail openin d, formed through shown.

L. The receiving dovetails @having enlarged entering portions a andlower sOeket-seatsf for the dovetails b, as and for the purposedescribed.

3. The spacing-lugs a, combined with7 and forming backs k to, thereceiving' dovetails I) to give strength to the bar at this point, asdescribed.

The above speeieation of my improvement in grate-bars for furnacessigned this 19th day Of J anuary, A. D. 1ST-1.

EDWARD MALLON.

Witnesses:

A. E. H. JOHNSON, J'. W. l-IAMIL'JJON J OHNSON.

